U.S. Army Lt. Gen. H Steven Blum, the chief of the National Guard Bureau, rides a Border Patrol horse during a visit to the U.S. border near Columbus, N.M., Nov. 29, 2006. Up to 6,000 National Guard troops are helping the Border Patrol secure the nation’s southern border in Operation Jump Start. jim.greenhill/flickr

For decades, the Border Patrol has relied on horses as an old-fashioned, low-tech solution to police U.S. borders. They offer what the Border Patrol refers to as a “tactical elevation advantage”—that is, agents can see better when they’re perched high on horseback.

They also have an edge in terms of longevity. While vehicles last for a few years, a horse can work for up to 17 consecutive years.

And the main draw for horses is that they can go where ATVs and trucks generally can’t: up steep rock faces and parsing thick brush. They’re also environmentally friendly; and ranchers tend to prefer Border Patrol trespassing on horseback to noisy quads or jeeps.